An increase in the mobile Internet speed due to the evolution of a network, such as LTE (long term evolution), and the highly improved performance of a mobile terminal brings about high-definition content which causes a sharp increase in the amount of traffic generated when reproducing mobile videos. The surge in wireless data traffic stems from an increase in the number of smartphone users, as well as mobile video and network evolution. Due to the rapid increase in the mobile data traffic, 80% of the mobile data traffic is generated on smartphones and mobile video traffic are expected to account for 60% of total mobile data traffic, respectively, in 2020. Such a sharp increase in the amount of wireless data traffic is attributed to an increase in the amount of mobile video traffic and the improvement in mobile video resolution. In fact, HD (high definition) video content is expected to account for 52% of global Internet protocol (IP) video traffic in 2018, up from 36% in 2013, while standard definition (SD) video content is expected to account for 37% thereof, down from 64% in 2013.
As a result of such an increase in the IP traffic, the actual global IP traffic in 2013 comprised 41% Wi-Fi, 3% cellular communication, and 56% wired communication, respectively, because of user data charge burdens.
Although there are various mobile video streaming services based on LTE unicast, most mobile video streaming users consume mobile video streaming services using Wi-Fi in order to avoid higher data charges, and thus only users in areas where Wi-Fi is not available use mobile video streaming services in a cellular environment such as LTE or the like.
FIG. 1 is a view illustrating the configuration of a general system for providing mobile video streaming services.
The system shown in FIG. 1 includes a content provider server 101 for providing content, a service provider server 103 for providing a mobile video service, a Wi-Fi network 105, a cellular network 107, such as an LTE network, and a user terminal 109.
In the example of FIG. 1, the user terminal 109 may use the mobile video streaming service by accessing the Wi-Fi network 105 or the cellular network 107 depending on the surrounding environment while using the mobile video streaming service.
The existing mobile video streaming service provides convenience to mobile-video service users through switching between heterogeneous networks, such as Wi-Fi and LTE. However, the currently provided mobile video streaming service provides a network switching function for the mobile video streaming service with a long buffering time when switching between heterogeneous networks. Therefore, it is difficult to provide smooth service because interruption of the service or deterioration of quality may occur when switching networks in the real-time mobile video service. In addition, smooth service cannot be provided in the existing mobile video streaming service because the network switch is performed without consideration of content and a transmission environment when switching between heterogeneous networks.